= System configuration & Kernel tweaks =

参数优化：/etc/sysctl.conf
{{{
net.ipv4.ip_default_ttl = 255
net.ipv4.icmp_echo_ignore_broadcasts = 1
net.ipv4.icmp_ignore_bogus_error_responses = 1

net.ipv4.tcp_max_tw_buckets = 262144
net.ipv4.ip_local_port_range = 1024  65535

# Do not use swap ASAP
vm.swappiness = 0

# TCP socket keepalive check every minute, if fail check every 10 seconds and 3 times
net.ipv4.tcp_keepalive_time = 60
net.ipv4.tcp_keepalive_intvl = 10
net.ipv4.tcp_keepalive_probes = 3

net.ipv4.tcp_fin_timeout = 30
}}}

参数优化：/etc/security/limits.conf
{{{
*   -   nofile      65535
*   -   nproc       65535
}}}

更多的参数优化，可参考如下：

http://cherokee-project.com/doc/other_os_tuning.html

http://tengine.taobao.org/document/benchmark.html